bertrau



L. F. BERTRAU.

HYDROCARBON BURNER AND FURNACE.

APPLICATION FILED MAY 2, I919, 1,320,973. Patented Nov. 4, 1919.

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HYDHOCARBON BURNER AND FURNACE.

n L won FILED MAYZ 1919 Patented Nov. 4, 1919.

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HYDROCARBON BURNER AND FURNACE.

APPLlCATlON FILED MAY 2. I919.

Patented Nov. 4, 1919.

3 SHEETS-SHEET 3 Ewuemtoz UNITED STATES PATENT onFroE.

LOUIS F. BERTRAU, OF COIlUMBUS, OHIO, ASSIGNOR TO CHAMPION KEROSENE- BURNER COMPANY, OF BENTON, OHIO, A CORPORATION OF OHIO. L

HYDROCARBON BURNER. AND FURNACE.

Application filed May 2, 1919. Serial No. 294,274.

State of Ohio, have invented certain new and useful Improvements in Hydrocarbon Burners and Furnaces; and I hereby declare that the following is a full, clear, and exact description thereof, referencebeing had to] the accompanying drawings, which form part of this specification.

This invention is a novel improvement in apparatus for burning kerosene and like fluid hydrocarbons. r

The objects of the inventlon are (l) to produce a simple, efficient and practical apparatus, which will reduce fluid hydrocarbons, such as kerosene, to a gaseous condition, and burn. same in such mannerthat all the fuel units in the kerosene 'will be utilized and there will practically be no an apparatus which requires but one valve to control the supply of ,fuel from theresein;

voir to the burner. I will hereinafter To enable art to fully i [understand and utilize the invention, and

adapt the same to'various purposes in the arts, I will describe" the-invention as applied to a furnace for heating rivets, as illustrated in the accompanying drawings, and the essentials of the invention, and novel combinations of parts and novel features of construction, for all of which I desire protec- I tion, are summarized in the claims.

The kerosene ispreferably supplied under air pressure to my gas generating and burning apparatus to insure a practically continuous and uniform supply thereof; and such apparatus produces an intense nonoxidizing heat rendering such apparatus particularly useful in mnmnfirm Wm. Boat- Specification of Letters Patent.

v To utilize such apparatus in a furnace forheating rivets and the like; and (4) to make efer to the apparatus as burning" keroseneynsing the word keroa' sene generically include various fluid, hydrocarbonsrhkeor akin to the ordinaryso-called' kerosene or coal oil? such as is. commonly used in-l'amps, and in oil burning furnaces...

Patented Nov. 4, 1919.

ing and cooking stoves for dwellings; also,

in furnaces,kilns and ovens in factories;

and in furnaces forheating rivets, and thelike; for the flame being free from oxidizing gases the rivets, for example, can be left in the furnace for an indefinite time without being overburned or oxidized.

In the accompanying drawings:

plete kerosene burning rivetheating furnace embodying the novel features of the invent1on.

Fig. 2 is a side view of Fig. 1. v

Fig. 3 is an enlargedvertical section on the line 3w-3, Fig. 2.

Fig. 4 is a top plan view of the generator and burner.

Fig. 5 is an endelevation of Fig. 4:.

Fig. 6 is an enlarged transverse sectional view on line 6-6, Fig. 4:.

. Fig. 7 is a greatly enlarged sectional View of the gas jet head.

The erosene gas generator and burner, forming an essential feature of this invention, comprises a U-shaped retort 1, which may be made out of gas-'pipe, detachably at-.

tached to and supported upon the exterior of an elongated hollow casting 2, the interior of which casting forms what I term a backing 2 in its upper side near one end there of, which is connected with the gas mixing tube 4 hereinafter referredto The casting 2 may be rectangular in cross section, and ispreferably arranged in a in any suitable manner, and is shown vas fastened to said casting by .retainerstraps 1 secured to the casting by screws 1 whereby the retort is supported at a. proper distance above the flange 2"; and said retort may be slightly spaced from the walls of the casting by any suitable means, as by verti cal flan or ribs 2 formed on the outer walls 0 the casting. y

In the'side and inner endwalls of the pressure gas-chamber C;'which chamber is "closed on all'sides except for an inlet openrectly opposite and in line W1 casting 2 adjacent the retort 1, and in close proximity thereto are formed numerous closely adjacent minute perforations 2*, as

shown in Figs. 3 and 6, through which perforations gases escape from the back pres sure gas chamber C and are burned to heat the retort as hereinafter explained.

One end of the retort 1 is connected by a reducing elbow 1, to the upper end of a vertically disposed reservoir or feeder 1, which may be formed of ordinary gas pipe, and which is connected with one end of a T 1", to the stem of which is connected the outlet end of a valve casing 1 containing a needle valve operable by a handle 1 and to the inlet of said needle valve casing is connected a pipe 1 leading to a suitable kerosene supply, such as a tank 7; hereinafter explained. A drain petcock 1 may be connected to the lower end of T 1 so that the retort 1 and feeder pipe 1 may be drained when desired.

The other end of the retort 1 is connected by a reducing elbow 1 with one end of a short pipe 1 the upper end of which is connected to a small T 1 (shown greatly magnified in Fig. 7) which is preferably disposed in a horizontal plane and is closed at its outer end by a plug 1', and its inner end is closed by a removable jet head 1". This jet head 1 is provided with a central jet aperture 1, which is very minute and preferabl cylindric and. uniform in contour, so that tie hot gases generated from the kerosene in the retort will escape in a small but forcible jet through the aperture 1 into the adjacent open end of a mixing tube 4, which may be formed of gas pipe, and is shown as supported in a horizontal position upon and above the castin 2 and di- 't% the aperture 1 in the 'et head.

As shown t e mixing tube 4 may be pro-- vided, at a oint suitably removed from-the jet head, wlth a T 4; the stem of which is connected with the upper end of a short pipe section 4', the lower end of which section is securely fitted to and engaged with the inlet opening 2 of the back-pressure chamber C. This section 4* serves both to (1) support the mixing tube 4 rigidly above and upon the casting 2, and also (2) as a means of communication between the mixing tube and the back-pressure chamber C.

he discharge end of the mixing tube 4:

- is connected to the member or members to which the inflammable aseous mixture formed in the mixing tube is to be delivered. In the example shown the discharge end of the mixing tube 4; is connected by an elbow 4:? to a downwardly extending pipe P, which conducts the gaseous mixture into the heating chamber F of a rivet heating furnace 5, hereinafter explained, upon the top of which the generator and burner is supported.

I preferably provide a housing plate 2, placed on top of the casting 2 and projecting beyond the edges thereof approximately as far as the flange? projects, and the edges burner or flange 2*, and from the jets 2 in close relation to the retort L and concentrate the heat from such flames upon said retort. The housing plate 2 may be provided with an opening 2 to permit the plate to be readily placed on top of the casting 2 after the nipple 4 is connected therewith; and it may be detachably secured in position on the casting 2 by a screw 2 The rivet heating furnace 5 may have exterior metal side walls 5*; and a metal top plate 5. This top plate has an extension 5 at one side upon which the casting 2 is partially supported, as shown, so that the discharge pipe 2t from the mixing'tube can enter the furnace chamber F through openings in the top wall of the furnace as shown. This furnace is thickly lined interiorly' with fire brick, as indicated at 5 the fire brick covering the ceiling, walls, sides and bottom of the furnace; except for a door opening in the front to permit access to the furnace chamber. This opening may be closed b any suitable means; a gravital door 5 eing shown slidably hung upon a rod 5' supported on brackets 5* attached to the end walls of the furnace as shown.

The pipe 4 discharges gas downwardly into the top of the furnace chamber E; suitable openings being formed in the top plate of the furnace and in the fire brick lining for the passage of the pipe 4:, and said pipe may be surrounded within such openings with a packing 4of suit-able non-heat conducting material, such as asbestos, to lessen the heating of the pipe, which is also protected by the fact that the burning gases are non-oxidizing.

The furnace 5 is shown as provided with a metal base plate 5 and supported upon thetop plate 6 of a suitable metal stand, having angle-iron legs 6 stiffened by braces 6*, 6 and ties 6. 7 Upon the latter is mounted a. tank 7 which is provided with a pressure air gage 7 and an air inlet valve 7 b adapted for connection with any suitablecompressed air supply,such as a hand pump, not shown, or the usual compressed air distributing system installed in the buildingv in which the furnace is used. This tank 7 is also provided with a fuel filling nipple 7 .5 and with a fuel outlet pipe 7 which preferably extends to the bottom of the tank and lar bushings -1 which may be placed in the stem of the T 4*- and rest upon the upper end of the pipe section 4:. Such interchangeable bushings 4 are provided having bores of different diameters, so that a bushing having an opening of the proper diam-' eter to permit the proper amount of gas to pass from the mixing tube l into the backpressure chamber C, can be used according to the size and capacity ofthe generator and burner. I

. In the construction shown the walls of the furnace chamber F and articularlythe bottom thereof, form a be e for the out;

rushing stream of the inflammable gaseous;

mixture and cause complete combustion thereof. -In actual use the furnace can be maintained at a high uniform heat, and objects placed'therein may be heated the desired temperature; butthe combustion is so perfect that the flame is non -oxidizable, and metal rivets, for example, placed in such furnace and heated toincandescencecan be maintained at such temperature fi:

oxidizati'on.

,7 Part of the gaseous mixture passes'from themixing tube 4 through the pipe 4: into the back-pressure chamber 0 in the casting 2, and issuing through the jets 1 are ignited and the resultant flames maintain the retort 1 at a sufliciently high temperature to thoroughly reduce the 'kerosene admitted therein to a gaseous condition, the gases escaping very forcibly therefrom through the minute aperture 1 in the jet head 1. The kerosene is fed under pressure and uniformly to the reservoir pipe 1; the

amount of the supply being regulated by the valve 1; and a'very slight opening-of this valve insures asufficient supply of kerosene'to the retort during the practical operation of the furnace.

The retort should not be over-flowed or over-supplied. with kerosene. The pipe 1 bei arranged vertically forms an intermediate reservoir for kerosene between the valve and the retort suflicient-to compensate for any fluctuation in sup ly, and the backpressure of the gases in t e retort operates upon the column of, kerosene in this reservoir and helps to control the supply, and

the air fcombusti le mixture.

' Part of this mixture passes into the back As shown in the drawings,

although the gases in the retort are highly heated the reservoir 1 remains cool.

In starting the apparatus the, hollowv flange or priming burner 2 may be filled with alcohol, or othersuitable inflammable oil or material, and ignited, and the resultant flame therefrom rapidly heats the retort until gases are generated therein sufficient to produce inflammable mixtures in the mixing tube 4, and supply gas to the jets 2 to maintain the heat of theretort after the. priming fluid has burned out.

The inlet Valve 1 should be opened slightly to let the reservoir 1 fill the kerosene and a small quantity flow into the retort 1 wherein it is quickly reduced to a gaseous condition by the heat and as the gases cannot escape backward they pass,

from the retort 1 through the pipe 1 and and escape in a minute forcible jet throu h .the aperture 1 in the jet head into t e open end of the mixing tube 4; the jet of .gas drawsair i-nto'this tube with it, and

therein form a highly as mixing pressure chamber C and escaping through the apertures -l is ignited by the burning priming fluid and assists in heating the retort, and thereafter maintains the heat of the retort after the priming fluid has burned Out The main body of the inflammable mixture passes on to the point of utilization. it passes through the pipe 4 into the furnace chamber F;

wherein it is ignited a d burns without smokei'or-odorr I i ltfiisessential that some means of bafliing the gaseous mixture be provided, as I have found that if the pipe 49 is turned so as to discharge directly into the open air-without obstruction, the gaseous mixturewill not burn but will dissipate, whereas if such gases are discharged into the chamber F, or baflled by being partially confined, or impacted against a aflling surface, they will burn freely and with intense heat, and the combustion will be comple When the gas generatingand burnin apparatus is used in connection with a 000 ring or heating stove, the gases issuin from the mixing tube 4 could be conducte to burner heads by bifurcated or'branched pipes sub stantially as shown for example in patent to Rusteberg No. 1,27 3,277 of July 23, 1918.

I have found that the relative proportionsof certain of the parts of the generator and burner are important for the tical operation thereof. In the apparatus illustrated in the drawings the reservoir pipe 1 is'about six inches in length between its connection with the needle'valve and its successful pracconnection to the elbow 1"; and about onefourth inch in internal diameter. The retort 1 is about three-eighths inch in internal diameter. The pipe 1 is about one-eighth inch in internal diameter; the aperture 1 in the jet head 1 about 67 B. and S. gage straight bore; the gas mixing tube 4 about one and one-fourth inches in internal diameter and the discharge pipe 4 could be of the same size. The nipple or pipe 4 should either be 'of about eleven-sixteenths of an inch in internal diameter; or if of larger diameter provided with a bushing or choke rink 4 as shown havingan opening about eleven-sixteenths of an 1nch in internal di-' ameter. The heating chamber F in the furnace is about twelve-by-nine-by-nine inches in size. The needle valve 1 should be about 15 degrees point and one-eighth of an inch in diameter; and the jet apertures in the casting 2 should be about one-eighth inch in diameter and drilled quite close together so as to provide numerous jet apertures, makin an almost continuous sheet of flame. preferably avoid the use of slits as the gases do not burn as well or uniformly issuing through slits as through small jet openings. With the proportions given the apparatus using ordinary kerosene after it is properly started will produce continuously sufficient gaseous mixture to maintain the entire furnace at a high temperature, suflicient to soften and almost lique the fire brick in the bot tom of the furnace chamber F and most directly exposed to the incoming gases from the pipe 4 y The proportions abovegiven for the relative sizes of different parts of the apparatus I have found after many tests to be sub-- stantially basic and generators and burners of difl'erent capacities and sizes may besuccessfully made, based upon the relative proportions of parts above given.

The rivet heating furnace shownis very. simple and practical and is readily ortable. and as it is light can be moved rom one' lace in a shop or facto to another, or f.

. romone floor of a buil ing to another,

without any special lifting apparatus; and

by reason of this portability the furnaceca-n be placed so that the heated rivets can" be easily thrown from the furnacedirectly to the riveters. Furthermore, rivets can be heated rapidly in this furnace and as the flame is non-oxidizin rivets, etc., will not be injured if left in tie furnace for an unusual length oftime, or such length of time as would burn them in an ordinary furnace or heating forge. Such furnace is very economical in fuel and can be operated with a great deal less kerosene per hour than prior types of oil burning rivet/heating furnaces.

While .the invention is shown adapted for a rivet heating furnace, I do not consider the invention limited to use in connection with such furnaces, and the kerosene gas adapted for many other purposes in the arts where a constant intense heat is desired.

With a so-called plumbers torch the retort 1 can be heated sufliciently to enerate gas and supply the jets 1 as quickl y as, or even more quickly than, can be done by burning alcohol in the primary burner flange 2". Therefore I do not consider the invention restricted to the use of the primar burner flange 2.

hat I claim is:

1. In a kerosene gas generating and burning apparatus, a casting having an internal backpressure gas chamber, a series of closely adjacent apertures in its sides, a gas inlet adjacent one end thereof, and an exterior projecting hollow priming burner flange on its lower side; a retort supported on the side of this casting above the priming burner flange; an air and gas mixing tube; a short pipe section supporting the mixing tube on the casting'and connecting the tube with the back pressure chamber, and a choke ring in said pipe-section; a supply pipe connected with said retort, a valve for regulating the flow of kerosene to the retort; a jet head connected with the discharge end of the retort adapted to direct gas generated in the retort into the mixing tube; a housing plate on thesaid casting overlying the re relatively the dimensions stated, a retort approximately three-eighths of an inchgin, "diameter; a-re'servoir pipe' approxima" 13 one-fourth of an inch in diameter connected I i with theinlet end of the retort; a supply pipe connected with said reservoir pipe; a

valve for-regulating. the flow of'kerosene Q of the retort=having proximately 67' B. and S. gage:

, 3. In a kerosene as generatingiand burnshaped retort approximately "three-eighths of an inch in diameter; a reservoir pipe approximately one-fourth of an inch in' di-v ameter connected with the inlet end of the tort; and a jet head having an aperture of approximately 6'2? B. and S. gage connected with the end of said reduced pipe.

4. In a kerosene gas generating and burning apparatus, a casting having an internal back pressure gas chamber, a series of --from the supply pipe to the reservoir; and a jet'headconnected with the discharge end;

a"jetaperture of aping apparatus having the following partsf 5 T of' relatively the dimensions stated, aU-

. connected with the discharge end of the re-- closely adjacent jet apertures in its sides, and a get inlet; a retort supported on the side of this casting adjacent the jet apertures; an air and gas mixing tube; a short pipe section connecting the mixing tube with the back pressure chamber; and a changeable choke-ring in said tube.

5. In a kerosene gas generating and burning apparatus having the following arts of relatively the dimensions stated, a ack pressure apertures in its sides; a retort approximately three-eighths of an inch in diameter; an air and gas mixing tube approximately one and one-fourth inches in diameter; a supply pipe connected with the inlet end of the retort; a valve for regulating the supply of kero-- sene; a jet head connected with the discharge end of the retort, having an aperture approximately 67 B. and S. gage adapted to direct a jet of gas generated in the retort into the mixing tube; a connection approximately eleven-sixteenths of an inch in diameter between the mixing tube and the said chamber; and means to conduct the inflammable mixture from the gas mixing tube to the point of utilization.

6. In a kerosene gas generating and burn ing apparatus having the followin parts of relatively the dimensions stated aback pressure gas chamber having a series of.

apertures in its sides; a retort approximately three-eighths of an inch in diameter; an air and gas mixing tube approximately one and one-fourth inches in diameter; a reservoirpipe approximately one-fourth of an inch in diameter connected with theinlet end of the retort; a supply pipe connected with said reservoir, a valve for regulating the flow of kerosene to the reservoir; a jet head having an aperture ap roximately 67 B. and S. gage connected wit the discharge end of the retort and adapted to direct gas generated in the retort into the mixing tube; a connection approximately eleven -sixteenths of an inch in diameter between the mixingtube and the said chamber; and means for conducting the inflammable mixture from the mixing tube to the point of utilization. j

7. In a kerosene gas generating and burning apparatus, a back pressure gas chamber having a series of apertures in its sides; a retort approximately three-eighths of an inch in diameter, an air and as mixing tube approximately one and oneourth inches in diameter; a vertically disposed reservoir pipe approximately one-fourth of an inch in diameter connected with the inlet end of the retort; a supply pipe connected with said reservoir; a valve for regulating the supply of kerosene from the supply pipe to the reservoir; a pipe approximately one eighth of an inch in diameter connected with the discharge end of the retort; and a jet gas chamber having a series of tween the mixing tube and the said chama her; and means for conducting the inflammable mixture from the gas mixing tube to the point of utilization.

8. 'A portable kerosene burning furnace having an interior heating chamber; a kerosene gas generator mounted upon said cas ing; means for directing the combustible mixture from said generator into the chamher; a portable stand upon which the furnace and generatorare mounted, a tank on said stand, and a pipe forcondu'cting kerosene under pressure from said tank to thegenerator.

9. In a kerosene gas generating and burning apparatus, an elongated casting whose interior forms an internal back-pressure gas chamber having a series of alined closely ad acent jet apertures in its sides and a gas inlet in its top adjacent oneend thereof; a retort supported on this casting adjacent the apertures; an air and as mixing tube above and extending paralleI with the casting; a short tube extending at right angles to the casting and tube and supporting the mixing tube on the casting and connecting it with the back-pressure chamber; means for supplying kerosene to said retort, a valve for regulating the supply of kerosene; a jethead connected with the discharge end of the retort and adapted to direct gas generated in the retort into the mixing tube; and means connected with the discharge end of the mixing tube to conduct inflammable mixture to the point of utilization.

10. In a kerosene gas generating and burning apparatus, an elongated casting whose interior forms an internal back-pressure gas chamber having a series of alined I closely adjacent jet apertures in its sides and v a gas inlet in i'tstop ad'acent one end thereof; a retort adjacent t e apertures; an air and gas mixing tube extending arallel with the casting; a short tube exten ing at right tube; and means connected with the discharge end of the mixing tube to conduct, inflammable mixture to the point of utilization.

11. In kerosene gas generating and burning apparatus, an elongated casting whose interior forms an internal back-pres- I of the retort; a jet-head connected with the" end of this reduced pipe and adapted to; direct generated gas into the mixing tube; and means connected with'thc' discharge end' sure gas chamber having a series of alined closely adjacent jet apertures in its sides and a as inlet in its top adjacent one end thereo a retortsupported on and partly surrounding this casting adjacent the apertures; an air and gas mixing tube above and extending parallel with the castin a short v tube extending at right angles to the casting and tube and attaching the mlxing tube to the casting and connect ng it with the back ressure chamber; a reservoir pipe connected with the inlet end of the retort; a supply pipe connected with said reservoir pipe; a va ve for regulating. the supply of kerosene from the supply pipe to the reservoir; a re duced pipe connected with the discharge end above the casting; a tubular connection be tween this mixing tube near one end thereof and the said chamber; a supply connected with one end of the U-shaped pipe; a valve for regulating thesupply of kerosene to the pipe. a jet-head 0 posite the inlet end of the mixing tube a erated in the'pipe into the mixin tube; a connection between the other end 0 the pipe and said jet-head; means for conducting the inflammable mixture from the gas mixing tube to-the point of utilization; and an abutment against which the inflammable mixture is discharged. j

13. A kerosene gas generating and burning apparatus comprisin a hollow horizontally disposed casting w ose interior forms a back-pressure gas chamber having a horia zontally alined series of closely adjacent gas apertures in its sidesand one end; a U- shaped retort exterior to and partly surrounding said casting and supported opposite the gas apertures therein; a horizontally disposed an and gas mixing tube above the casting; a lateral connection between this I tube near one end thereof and the said chamber; a kerosene supply connected with one end of the U-shaped' retort; a valve for regulating the supply of kerosene; a jet-head opposite the i et "endxof the mixing tube,

' adapted to direct gas generated in the retort into the air and gas mixing tube; a connection between the other end of the retort and casting adjacent housing plate mo'iuited on the said castlng charged.

tube

tube on the casting and eonnectin apted'to direct gas gen-' said jet-head; means for conducting the inflammable mixture from the gas mixing tube to the point of utilization; and an abutment against which the inflammable mixture is discharged.

14. In a kerosene gas generating and burning apparatus, a single casting whose 7 interior forms an internal back-pressure gas chamber, havmg a series of alined apertures in its sides, and a gas inlet adjacent one end; a U-shaped retort partly surround-mg the the apertures therein; a

above and overlying the retort; an air and gas mixing tube laterally connected with the gas inlet of the casting; a jet-head adapted to direct gas generated in the retort. 7 into the inlet end of the air and gas mixing tube; a kerosene-supply connected with one end of the retort; a valve for regulating the supply of kerosene; means for conducting gas from the other end of the retort to the jet-head; means for conducting the inflammable mixture from themixing tube to the 'pointof utilization; and an abutment against which the inflammable mixture dis 15 In a kerosene gas generating and burning apparatus, an elongated casting whose interior forms an internal back pressure gas chamber having a series of alined closely adjacent jet a ertures in its sides, a gas inlet'in its iLOPHdJ'LCBIlt one end thereof;

[a U-shaped retort supported on and partly surroun ing this casting adjacent the apertures; anair and gas mixing tube above the casting; a short tube supporting the mixing it with the back-pressure chamber; a houslng plate on the said casting above and overlyin the retort; a reservoir pipe connected with the inlet end of the retort; a supply pipe connected with said reservoir; a valve for regulating the flow of. kerosene from the supply pipe to the reservoir; a reduced pipe connected with the discharge end of the retort; a jet-head connected with the end of this reduced pipe and adapted to direct gas generated in the retort into the air and as mixing tube; and means connected wit the dis charge end of the mixing tube to conduct the inflammable mixture to the point of utilization. v

16. In a kerosene gas generating and burning apparatus, a casting having an internal back-pressure gas chamber and a series of closely adjacent jet apertures in its sides; a retort at the side of this casting opposite the jet apertures; an air and gas-mixing tube mounted above the casting; a sup: ply pipe connected with the inlet end of the retort; a valve for regulating'the supply of kerosene to the retort; a jet-head connected With the discharge end of the retort adapted to direct a jet of gas generated in the retort into the air and gas mixing tube; a removable housing plate mounted on the said casting and overlying the retort.

stantially as described.

apertures in its sides; a retort at the, side of th1s castmg opposite the jet apertures; an

air and gas mixing tube; a tubular connec tion between the mixing tube and said gas chamber; a removable check ring in this connection; a supply pipe connected with the inlet of the retort; a valve for regulating the supply of kerosene; and means to direct the gas generated in the retort into the air and gas mixing tube, substantially as described.

In testimony that I' claim the foregoing as my own, I affix my signature.

LOUIS F. BERTRAU. 

